Rotary piston internal combustion engine



ROTARY PISTON INTERNAL COMBUSTION ENGINE Filed Sept. 24, 1962 5Sheets-Sheet 1 Fig] Inventor.- Georg Tang Hut/'2 Nov. .9, 1965 G.JUNGBLUTH 3,216,405

ROTARY PISTON INTERNAL COMBUSTION ENGINE Filed Sept. 24, 1962 5Sheets-Sheet 2 Inventor: Gen/ g Tang bluih by W Nov. 9, 1965 G.JUNGBLUTH ROTARY PISTON INTERNAL COMBUSTION ENGINE 3 Sheets-Sheet 3Filed Sept. 24, 1962 Inventor: Georg .Tungbluth by W United StatesPatent 3,216,405 ROTARY PISTON INTERNAL COMBUSTION ENGINE GeorgJungbluth, Cologne-Deutz, Germany, assignor to Klockner Humboldt DeutzAktieugesellschaft, Cologne-Deutz, Germany Filed Sept. 24, 1962, Ser.No. 225,920 Claims. (Cl. 123-8) The present invention relates to arotary piston internal combustion engine with an engine body confiningan inner rotor and together with the latter forming the workingchambers, while the inner rotor is eccentrically journalled in theengine body and has its enveloping surface provided with at least twoaxis parallel apex edges. The rotary movement of the inner rotor on aneccentric is brought about by teeth on the inner rotor meshing withteeth on the engine body.

With heretofore known rotary piston internal combustion engines, thespeed transmission between the eccentric shaft and the inner rotor iseffected by a transmission which comprises a stationary gear withexternal teeth connected to the engine body, and also comprises a gearwith inner teeth on the inner rotor which lastmentioned gear rolls onthe gear with external teeth. With the heretofore known rotary pistoninternal combustion engines, the diameter of the gear connected to thehousing is relatively small. Consequently, also the eccentric shaftwhich extends through the gear on the housing has a very small diameter.This construction together with the higher pressures occurring in theengine and the slight eccentricity of the eccentric shaft, brings abouta very high specific load on the eccentric shaft.

It is therefore an object of the present invention to provide a rotarypiston internal combustion engine which will overcome theabove-mentioned drawback.

It is another object of this invention to provide a rotary pistoninternal combustion engine of the above-mentioned type in which thediameter of the eccentric shaft may be freely selected within certainlimits.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawings, in which:

FIGURE 1 illustrates a longitudinal section through a first embodimentof a rotary piston internal combustion engine according to theinvention;

FIG. 2 is a section similar to FIGURE 1 in which the gears with internalteeth employed in FIGURE 1 have been replaced by gears with externalteeth;

FIG. 3 is a section along the line IIIIII of FIG. 1;

FIG. 4 is a further modification.

The internal combustion engine according to the present invention ischaracterized primarily in that between the teeth of the inner rotor anda stationary gear there is provided a planetary gear wheel setcomprising a smaller and a larger pinion, said set being rotatable on ashaft connected to the eccentric. In this way, the diameter of theeccentric shaft may be freely selected within certain limits. This is ofparticular importance when it is intended to drive a rotary pistoninternal combustion engine operating at high compression with fuelinjection because in such an instance the eccentric shaft and thebearing therefor will be subjected to still higher loads than is thecase with a heretofore known rotary piston internal combustion engineequipped with a carburetor.

Referring now to the drawing in detail, and FIG. 1 thereof inparticular, the arrangement shown therein comprises an eccentric 1 on aneccentric shaft 2. Journalled on the eccentric 1 is the inner rotor orrotary piston 3 of the rotary piston internal combustion engine.Connected to the internal rotor 3 is a gear 4 which may 3,216,405Patented Nov. 9, 1965 form one piece with the internal rotor 3 and hasinner teeth 5. In the housing or engine body 12 which with the rotarypiston 3 forms the working chambers of the internal combustion enginethere is arranged a stationary gear .6 with internal teeth. As will beevident from the drawing, the gears 4 and 6 are drivingly interconnectedby means of a planetary gear set 7. The planetary gear set 7 comprises asmaller pinion 7a and a larger pinion 7b and is rotatable on a shaft 8connected to the eccentric 1. In conformity with FIG. 1, gear 4 mesheswith the pinion 70, whereas gear 6 meshes with the pinion 7b of theplanetary gear set 7.

The arrangement of FIG. 2 differs from that of FIG. 1 in that instead ofthe gears with internal teeth, gears with external teeth are employed.Thus, a gear 9 is connected to the inner rotor 3 while a gear 10 isfixedly connected to the engine body 12. Both gears 9 and 10 arelikewise drivingly interconnected through a planetary gear set 11 with alarger pinion 11a and a smaller pinion 1112. Gear 10 meshes with pinion11a, whereas gear 9 meshes with pinion 11b.

As will be evident from FIGS. 1 and 2, the diameter of the entire enginecan be kept small due to the arrangement of the planetary gear setsadjacent the eccentric 1 within the range of the largest radialextension of the eccentric from the central longitudinal axis of theeccentric shaft. When an eccentric is employed which, when viewing theentire circumference of the eccentric shaft, protrudes beyond thediameter of the eccentric shaft, a plurality of planetary gear sets maybe connected to the eccentric. The eccentric may, as far as its radialextension is concerned, be so dimensioned that also within the range ofthe smallest radial extension of the eccentric from the centrallongitudinal axis of the eccentric, a planetary gear set may beprovided.

FIG. 3 shows the arrangement of a plurality of planetary gear sets 7 onthe wide portion of the eccentric. FIG. 4 shows that also within therange of the smallest radial extension of the eccentric from thelongitudinal central axis of the eccentric, a planetary gear set 13 maybe provided.

In addition to the different arrangements of the planetary gear sets,FIGS. 3 and 4 also show that the illustrated rotary piston internalcombustion engine is of a type in which the inner rotor 3 is designed inconformity with the inner enveloping curve 14 of the epitrochoid. Thisinner enveloping curve 14 forms the inner confining surface of theengine body 12. The inner enveloping surface 14 of the engine body 12and the enveloping surface 15 of the inner rotor 3 confine the workingchambers of the engine.

The rotary piston internal combustion engine as illustrated in thedrawing is of the type in which the inner rotor is designed inconformity with the inner enveloping curve of an epitrochoid. Asstarting curve, there may be selected a two-arched epitrochoid. Thisforms the inner confining surface of the engine body. Between the innerconfining surface of the engine body and the enveloping surface of theinner rotary there are formed the working chambers of the engine.

The invention is highly advantageous particularly with all rotary pistoninternal combustion engines in which, due to the kinematic conditionsinherent thereto, the gear through which the eccentric shaft extends,will have a small diameter when said gear is in direct connection withthe teeth of the inner rotor.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular constructions shown in the drawings butalso comprises any modifications within. the scope of the appendedclaims.

What I claim is:

1. A rotary piston internal combustion engine which comprises: a firstengine member forming an outer engine body, a rotatable shaft journalledin said first engine member and having an eccentric thereon, a secondengine member eccentrically arranged within said first engine member androtatably journalled on said eccentric, said second engine member beingrotatable relative to said first engine member while confining workingchambers therewith, first internal gear means connected to the outsideof said second engine member, second internal gear means stationarilyarranged on said first engine member in coaxial relationship to saidshaft, said second gear means having a larger pitch diameter than saidfirst gear means, compound planet pinion means comprising a first pinionportion and a second pinion portion firmly connected to each other, saidfirst pinion portion being smaller than said second pinion portion andmeshing with said first gear means while said second pinion portionmeshes with said second gear means, and stud means fixedly connected toone end of said eccentric and rotatably supporting said compound planetpinion means.

2. A rotary piston machine, especially an internal combustion enginewhich comprises; a housing member having a cavity therein which incross-section is a multiarched surface in the form of a epitrochoid, endWall portions fixed to said housing and closing said cavity at the ends,a shaft extending through said cavity and journalled on said end wallportions, an eccentric within said cavity fixed to said shaft andprojecting radially from said shaft at all points, a multi-corneredpiston journalled on said eccentric and slidably engaging the saidsurface of the cavity, a ring gear fixed to the inside of one of saidend wall portions within the cavity and concentric with said shaft, aninternal gear portion fixed on said piston, and a compound planet pinionrotatably mounted on one side of said eccentric and having one portionmeshing with said ring gear and another portion meshing with saidinternal gear.

3. A rotary piston machine according to claim 2, in which said ringgear, said internal gear and said compound planet pinion are in theirentirety located within the confines of said piston, a ring gear fixedto the inside of one of said wall portions within the cavity andconcentric with said shaft, an internal gear carried by the piston, andcompound planet pinion means mounted rotatably on one end face of saideccentric and meshing with said ring gear and said internal gear, saidcompound planet pinion means comprising a plurality of compound planetpinions spaced circumferentially of said eccentric and each comprisingone portion meshing with said ring gear and another portion meshing withsaid internal gear.

4. A rotary piston machine according to claim 2, in Which said compoundplanet pinion is receivable within the radial confines of that portionof said eccentric which extends the smallest distance outwardly fromsaid shaft.

5. A rotary piston machine, especially an internal combustion enginewhich comprises; a housing member having a cavity therein which incross-section is a multiarched surface in the form of a epitrochoid, endwall portions fixed to said housing and closing said cavity at the ends,a shaft extending through said cavity and journalled on said end wallportions, an eccentric Within said cavity fixed to said shaft andprojecting radially from said shaft at all points, a multi-corneredpiston journalled on said eccentric and slidably engaging the saidsurface of the cavity, a ring gear fixed to the inside of one of saidwall portions within the cavity and concentric with said shaft, aninternal gear carried by the piston, and compound planet pinion meansmounted rotatably on one end face of said eccentric and meshing withsaid ring gear and said internal gear, said compound planet pinion meanscomprising a plurality of compound planet pinions spacedcircumferentially of said eccentric and each comprising one portionmeshing with said ring gear and another portion meshing with saidinternal gear.

References Cited by the Examiner UNITED STATES PATENTS 2,970,042 4/61Bentele 123-8 FOREIGN PATENTS 19,254 1934 Australia. 612,579 11/48 GreatBritain.

142,829 12/30 Switzerland.

SAMUEL LEVINE, Primary Examiner.

JOSEPH H. BRANSON, Jn., KARL I. ALBRECHT,

Examiners.

1. A ROTARY PISTON INTERNAL COMBUSTION ENGINE WHICH COMPRISES: A FIRSTENGINE MEMBER FORMING AN OUTER ENGINE BODY, A ROTATABLE SHAFT JOURNALLEDIN SAID FIRST ENGINE MEMBER AND HAVING AN ECCENTRIC THEREON, A SECONDENGINE MEMBER ECCENTRICALLY ARRANGED WITHIN SAID FIRST ENGINE MEMBER ANDROTATABLY JOURNALLED ON SAID ECCENTRIC, SAID SECOND ENGINE MEMBER BEINGROTATABLE RELATIVE TO SAID FIRST ENGINE MEMBER WHILE CONFINING WORKINGCHAMBERS THEREWITH, FIRST INTERNAL GEAR MEANS CONNECTED TO THE OUTSIDEOF SAID SECOND ENGINE MEMBER, SECOND INTERNAL GEAR MEANS STATIONARILYARRANGED ON SAID FIRST ENGINE MEMBER IN COAXIAL RELATIONSHIP TO SAIDSHAFT, SAID SECOND GEAR MEANS HAVING A LARGER PITCH DIAMETER THAN SAIDFIRST GEAR MEANS, COMPOUND PLANET PISTON MEANS COMPRISING A FIRST PINIONPORTION AND A SECOND PINION PORTION FIRMLY CONNECTED TO EACH OTHER, SAIDFIRST PINION PORTION BEING SMALLER THAN SAID SECOND PINION PORTION ANDMESHING WITH SAID FIRST GEAR MEANS WHILE SAID SECOND PINION PORTIONMESHES WITH SAID SECOND GEAR MEANS, AND STUD MEANS FIXEDLY CONNECTED TOONE END OF SAID ECCENTRIC AND ROTATABLY SUPPORTING SAID COMPOUND PLANETPINION MEANS.